Last updated on May 26th, 2025
Roman numerals are a way of expressing numbers using symbols. I, V, X, L, C, D, and M are the symbols we use. Roman numerals are used in royal titles, book names, sequences, and so on. Here we will discuss Roman numerals, rules, and examples.
The royal titles, such as Henry I, Henry II, and so on, use Roman numerals. Have you noticed the names and wondered what these symbols (I and II) represented? Those are Roman numerals. Earlier, people used to count using fingers, sticks, bones, etc. As life became more complex, a standard form was required to count. Ancient Romans used the Roman numeral system to count. I (1), V (5), X (10), L (50), C (100), D (500), and M (1000) are the symbols we use to count.
In Roman numerals, we use DCCIX to represent 709, where D (500), CC (200), and IX (9). Let’s learn more about Roman numerals and how we write them.
There are certain basic rules to write a number in Roman numerals. In this section, let’s discuss some basic rules that need to be remembered when writing a number in Roman numerals.
Rule 1: Addition Method
The addition method is used when a smaller number is placed after a larger number. For example, XI → X + I → 10 + 1 = 11.
Rule 2: Repetition Method
To write a large number, certain Roman numerals can be repeated up to three times. For example, III → 3.
Rule 3: Subtraction Method
If a small number precedes a large number in Roman numerals, we subtract the smaller number from the larger number. For example, IX → X - I → 10 - 1 = 9.
Rule 4: Limitation Rule
The symbols cannot be repeated more than three times, and some symbols like V, L, and D cannot be repeated. For example, we won't write VV for 10; instead, we use X, and for 8, we write VIII, not IIIIIIII.
Let’s now learn how to write 709 in Roman numerals. Follow these methods to write the number in Roman numerals.
In the expansion method, based on place value, the number is broken down. In this section, we will learn how to write 709 in Roman numerals using the expansion method.
To write 709 in Roman numerals, follow the steps:
Step 1: Break the number based on place value. Place values are ones, tens, hundreds, etc.
For 709, we write it as 500 + 200 + 9.
Step 2: Converting the numbers into Roman numerals:
500 in Roman numerals — D
200 in Roman numerals — CC
9 in Roman numerals — IX
Step 3: Combine the Roman numerals together.
Therefore, 709 in Roman numerals is D (500) + CC (200) + IX (9) = DCCIX.
Students make mistakes when writing a number in Roman numerals. To master Roman numerals, we can learn a few common mistakes and the ways to avoid them.
A historian is analyzing ancient Roman artifacts. She finds a record stating that the Romans built CDIX aqueducts in one year and CCC aqueducts in another. How many aqueducts were built in total?
The total number of aqueducts built is DCCIX.
To find the total number, add the two amounts of aqueducts:
CDIX = 409
CCC = 300
409 + 300 = 709
709 in Roman Numerals is DCCIX.
An ancient scroll mentions a legion of soldiers who marched DCCIX miles in total over XX days. Determine the average distance marched per day.
The average distance marched per day is XXXV.
To find the average distance per day, divide the total distance by the number of days:
DCCIX = 709
XX = 20
709 / 20 = 35
35 in Roman Numerals is XXXV.
A mathematician writes a paper comparing the values of two ancient coins, one valued at CD and the other at CCCIX. What is the difference in value between the two coins?
The difference in value is XCI.
The difference is calculated by subtracting the smaller value from the larger value:
CD = 400
CCCIX = 309
400 - 309 = 91
91 in Roman Numerals is XCI.
An author is writing a novel set in ancient Rome and mentions a feast that lasted for DCCIX minutes. How many hours and minutes did the feast last?
The feast lasted for XI hours and XLIX minutes.
To convert minutes to hours and minutes, divide the total minutes by 60:
DCCIX = 709
709 / 60 = 11 hours and 49 minutes
11 in Roman Numerals is XI and 49 in Roman Numerals is XLIX.
Calculate the sum of two Roman years, MCMLXX and DCCCXXXIX, and express the result in Roman numerals.
The sum of the years is MMCMIX.
Sum is the result of adding two numbers:
MCMLXX = 1970
DCCCXXXIX = 839
1970 + 839 = 2809
2809 in Roman Numerals is MMCMIX.
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
: She loves to read number jokes and games.